Brunswick black
definition: See Japan black.

Brunswick black is a 15 letter word that begins with a B and ends in a K

Frankfort black
definition: A black pigment used in copperplate printing
Prepared by burning vine twigs the lees of wine etc.
Frankfort black is a 15 letter word that begins with a F and ends in a K

Plimsoll's mark
definition: A mark conspicuously painted on the port side of all British sea-going merchant vessels
To indicate the limit of submergence allowed by law; -- so called from Samuel Plimsoll by whose efforts the act of Parliament to prevent overloading was procured.
Plimsoll's mark is a 15 letter word that begins with a P and ends in a K

Stumbling-block (n.)
definition: Any cause of stumbling
Perplexity or error.
Stumbling-block is a 15 letter word that begins with an S and ends in a K

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